A variety of automated systems currently exist for controlling window covering systems, lighting systems, heating, ventilation, and air conditioning (HVAC) systems, and the like. However, these systems may be limited in their ability to respond to rapidly changing local or micro-climatic sky conditions (such as moving clouds, sunrise, sunset, and so forth), or to effectively predict future sky conditions. Accordingly, improved intelligent building control systems are desirable.
Prior approaches to sky camera systems typically utilized an expensive HDR camera and fisheye lens. One problem with this approach is that there is significant distortion in the evaluation of vertical sky conditions at the angles which the HDR camera must look to for assessing clouds towards the horizon. In particular, it is difficult to understand the true transparency, boundaries and movement of the clouds because the camera is looking at such a sharp angle. Thus, as prior systems try to get more forecasting capability out of the camera images, the prior systems are ultimately limited by, among other factors, the poor angle of view the system has on distant clouds. Accordingly, improved sky camera systems are desirable.